:root {
  color-scheme: dark;
  --canvas: #07111f;
  --canvas-soft: #0a1626;
  --surface: #0e1c2d;
  --surface-raised: #13243a;
  --line: #263a52;
  --line-soft: #172b42;
  --text: #edf4fb;
  --muted: #96a8bc;
  --faint: #667a91;
  --accent: #4a8df6;
  --accent-strong: #77aaff;
  --success: #4fd184;
  --radius: 18px;
  --content: min(1180px, calc(100vw - 40px));
  --sans: -apple-system, BlinkMacSystemFont, "PingFang SC", "Microsoft YaHei", "Segoe UI", sans-serif;
}

* { box-sizing: border-box; }
html { scroll-behavior: smooth; background: var(--canvas); }
body { margin: 0; overflow-x: hidden; background: var(--canvas); color: var(--text); font-family: var(--sans); -webkit-font-smoothing: antialiased; }
a { color: inherit; text-decoration: none; }
button { color: inherit; font: inherit; }
section[id] { scroll-margin-top: 86px; }

.site-header {
  position: sticky;
  top: 0;
  z-index: 20;
  height: 68px;
  display: grid;
  grid-template-columns: 1fr auto 1fr;
  align-items: center;
  gap: 28px;
  padding: 0 max(22px, calc((100vw - 1180px) / 2));
  border-bottom: 1px solid rgb(38 58 82 / .72);
  background: rgb(7 17 31 / .9);
  backdrop-filter: blur(16px);
}

.brand { display: inline-flex; align-items: center; gap: 10px; width: max-content; font-size: 16px; font-weight: 650; }
.brand img { width: 62px; height: 25px; object-fit: contain; filter: invert(1); mix-blend-mode: screen; }
.site-header nav { display: flex; align-items: center; gap: 30px; color: var(--muted); font-size: 14px; }
.site-header nav a, footer a { transition: color .2s ease; }
.site-header nav a:hover, footer a:hover { color: var(--text); }
.header-download { justify-self: end; padding: 9px 16px; border: 1px solid var(--line); border-radius: 999px; background: var(--surface); font-size: 13px; font-weight: 650; }
.header-download:hover { border-color: var(--accent); }

.hero {
  width: var(--content);
  min-height: calc(100dvh - 68px);
  display: grid;
  grid-template-columns: .82fr 1.18fr;
  align-items: center;
  gap: clamp(42px, 6vw, 88px);
  margin: 0 auto;
  padding: 76px 0 58px;
}

.eyebrow { margin: 0 0 18px; color: var(--accent-strong); font-size: 12px; font-weight: 700; letter-spacing: .12em; text-transform: uppercase; }
.hero h1 { max-width: 600px; margin: 0; font-size: clamp(48px, 5vw, 72px); line-height: 1.05; letter-spacing: -.055em; }
.hero-summary { max-width: 520px; margin: 24px 0 0; color: var(--muted); font-size: 18px; line-height: 1.7; }
.hero-actions { display: flex; gap: 12px; margin-top: 34px; }
.download-button { min-width: 152px; height: 50px; padding: 0 20px; border: 1px solid var(--line); border-radius: 999px; cursor: pointer; font-weight: 700; transition: transform .2s ease, border-color .2s ease, background .2s ease; }
.download-button:active, .header-download:active, .download-option:active { transform: translateY(1px); }
.download-button.primary { border-color: var(--accent); background: var(--accent); color: #07111f; }
.download-button.primary:hover { background: var(--accent-strong); }
.download-button.secondary { background: transparent; }
.download-button.secondary:hover { border-color: var(--accent); }

.capture-demo { overflow: hidden; border: 1px solid var(--line); border-radius: var(--radius); background: var(--surface); box-shadow: 0 28px 80px rgb(2 8 18 / .4); }
.demo-titlebar { min-height: 58px; display: grid; grid-template-columns: auto 1fr auto; align-items: center; gap: 18px; padding: 0 20px; border-bottom: 1px solid var(--line); color: var(--muted); font-size: 12px; }
.demo-titlebar strong { color: var(--success); font-size: 11px; }
.window-controls { display: flex; gap: 7px; }
.window-controls i { width: 10px; height: 10px; border-radius: 50%; background: #31455d; }
.window-controls i:first-child { background: #f76770; }
.window-controls i:nth-child(2) { background: #f7c44d; }
.window-controls i:last-child { background: #4fd184; }
.demo-body { display: grid; grid-template-columns: 166px 1fr; min-height: 430px; }
.demo-steps { display: flex; flex-direction: column; gap: 6px; padding: 18px 12px; border-right: 1px solid var(--line); background: var(--canvas-soft); }
.demo-steps { scrollbar-width: none; }
.demo-steps::-webkit-scrollbar { display: none; }
.demo-steps button { padding: 12px 13px; border: 0; border-radius: 10px; background: transparent; color: var(--muted); cursor: pointer; text-align: left; transition: background .2s ease, color .2s ease; }
.demo-steps button:hover { color: var(--text); }
.demo-steps button.is-active { background: var(--surface-raised); color: var(--text); }
.demo-stage { display: flex; flex-direction: column; justify-content: space-between; padding: 30px; }
.stage-status { display: flex; align-items: baseline; justify-content: space-between; gap: 18px; }
.stage-status span:first-child { color: var(--text); font-size: 22px; font-weight: 700; }
.stage-status span:last-child { max-width: 220px; color: var(--muted); font-size: 12px; text-align: right; }
.signal-map { display: grid; grid-template-columns: auto 1fr auto 1fr auto; align-items: center; gap: 12px; margin: 34px 0; }
.signal-node { display: grid; place-items: center; min-width: 74px; min-height: 74px; border: 1px solid var(--line); border-radius: 16px; background: #102139; color: #cfe0f4; font-size: 12px; }
.signal-line { height: 1px; background: linear-gradient(90deg, var(--line), var(--accent), var(--line)); transform-origin: left; }
.event-preview { display: grid; grid-template-columns: 90px 1fr; gap: 12px 18px; padding: 18px; border: 1px solid var(--line-soft); border-radius: 14px; background: #0b1829; font-size: 12px; }
.event-preview span { color: var(--faint); }
.event-preview strong { color: #dce8f4; font-weight: 550; }

.trust-strip { width: var(--content); display: grid; grid-template-columns: repeat(4, 1fr); margin: 0 auto; border-top: 1px solid var(--line); border-bottom: 1px solid var(--line); }
.trust-strip div { min-height: 110px; display: flex; flex-direction: column; justify-content: center; gap: 8px; padding: 20px 24px; }
.trust-strip div + div { border-left: 1px solid var(--line); }
.trust-strip strong { font-size: 15px; }
.trust-strip span { color: var(--muted); font-size: 12px; line-height: 1.5; }

.section { width: var(--content); margin: 0 auto; padding: 132px 0; }
.section-heading { max-width: 720px; margin-bottom: 46px; }
.section-heading h2, .capability-intro h2, .security h2, .download-section h2 { margin: 0; font-size: clamp(38px, 4.3vw, 60px); line-height: 1.08; letter-spacing: -.045em; }
.section-heading p, .capability-intro > p:not(.eyebrow), .security-statement > p:not(.eyebrow), .download-copy > p:not(.eyebrow) { max-width: 620px; margin: 18px 0 0; color: var(--muted); font-size: 16px; line-height: 1.7; }

.usecase-grid { display: grid; grid-template-columns: 1.4fr .9fr; grid-template-rows: 1fr 1fr; gap: 16px; }
.usecase-grid article { position: relative; overflow: hidden; border: 1px solid var(--line); border-radius: var(--radius); transition: transform .25s ease, border-color .25s ease, background .25s ease; }
.usecase-grid article:hover { border-color: #4777b8; transform: translateY(-4px); }
.usecase-main { grid-row: 1 / 3; min-height: 520px; display: flex; flex-direction: column; justify-content: flex-end; padding: 42px; background: linear-gradient(155deg, #142b49, #0d1b2b 58%); }
.usecase-main::before { content: ""; position: absolute; inset: 36px 36px auto auto; width: 160px; height: 160px; border: 1px solid rgb(119 170 255 / .35); border-radius: 50%; box-shadow: inset 0 0 0 28px rgb(74 141 246 / .06), inset 0 0 0 58px rgb(74 141 246 / .04); }
.usecase-side { min-height: 252px; padding: 32px; background: var(--surface); }
.usecase-identity:hover { background: #122742; }
.usecase-replay:hover { background: #142234; }
.case-number { color: var(--accent-strong); font-size: 11px; font-weight: 700; letter-spacing: .08em; }
.usecase-grid h3 { max-width: 520px; margin: 16px 0 0; font-size: clamp(24px, 2.5vw, 36px); line-height: 1.18; letter-spacing: -.025em; }
.usecase-side h3 { font-size: 24px; }
.usecase-grid p { max-width: 560px; margin: 16px 0 0; color: var(--muted); line-height: 1.65; }
.case-flow { display: grid; grid-template-columns: auto 1fr auto 1fr auto; align-items: center; gap: 12px; margin-top: 60px; color: #c7d7e8; font-size: 12px; }
.case-flow i { height: 1px; background: var(--line); }

.capability-story { display: grid; grid-template-columns: .72fr 1.28fr; gap: 84px; align-items: start; }
.capability-intro { position: sticky; top: 112px; }
.capability-nav { display: grid; gap: 6px; margin-top: 34px; }
.capability-nav button { display: flex; align-items: center; min-height: 43px; padding: 0 14px; border: 0; border-left: 2px solid var(--line); background: transparent; color: var(--faint); cursor: pointer; text-align: left; transition: color .2s ease, border-color .2s ease, background .2s ease; }
.capability-nav button.is-active { border-color: var(--accent); background: rgb(74 141 246 / .08); color: var(--text); }
.capability-list { display: grid; gap: 24px; }
.capability-panel { min-height: 520px; display: flex; flex-direction: column; justify-content: flex-end; padding: 36px; border: 1px solid var(--line); border-radius: var(--radius); background: var(--surface); }
.capability-panel h3 { margin: 30px 0 0; font-size: 28px; letter-spacing: -.02em; }
.capability-panel p { max-width: 620px; margin: 14px 0 0; color: var(--muted); line-height: 1.7; }
.capability-visual, .privacy-visual, .queue-visual, .identity-visual { flex: 1; min-height: 240px; display: flex; align-items: center; justify-content: center; gap: 14px; border: 1px solid var(--line-soft); border-radius: 16px; background: #0a1728; }
.signal-visual span, .privacy-visual span, .queue-visual span, .identity-visual span { padding: 12px 16px; border: 1px solid var(--line); border-radius: 12px; color: #cad9e9; font-size: 12px; }
.signal-visual span:nth-child(2) { transform: translateY(-28px); }
.signal-visual span:nth-child(3) { transform: translateY(20px); }
.privacy-lock { display: grid; place-items: center; width: 88px; height: 88px; border-color: var(--accent) !important; border-radius: 50% !important; }
.privacy-visual i { width: 1px; height: 90px; background: var(--line); }
.queue-visual i, .identity-visual i { width: 70px; height: 1px; background: linear-gradient(90deg, var(--line), var(--accent)); }

.capability-marquee { overflow: hidden; padding: 24px 0; border-top: 1px solid var(--line); border-bottom: 1px solid var(--line); background: var(--canvas-soft); }
.marquee-track { width: max-content; display: flex; gap: 10px; padding-left: 10px; animation: marquee 30s linear infinite; }
.marquee-track span { padding: 10px 16px; border: 1px solid var(--line); border-radius: 999px; color: #bdccdc; font-size: 12px; white-space: nowrap; }
@keyframes marquee { to { transform: translateX(-50%); } }

.security { display: grid; grid-template-columns: .9fr 1.1fr; gap: 86px; align-items: start; }
.security-statement { position: sticky; top: 112px; }
.security-rules { border-top: 1px solid var(--line); }
.security-rules article { min-height: 176px; display: grid; grid-template-columns: 160px 1fr; gap: 28px; align-items: center; padding: 30px 4px; border-bottom: 1px solid var(--line); }
.security-rules strong { font-size: 21px; }
.security-rules p { margin: 0; color: var(--muted); line-height: 1.7; }

.download-section { display: grid; grid-template-columns: .9fr 1.1fr; gap: 88px; padding-bottom: 150px; }
.guide-toggle { margin-top: 28px; padding: 0; border: 0; border-bottom: 1px solid var(--accent); background: transparent; color: var(--accent-strong); cursor: pointer; }
.install-guide { margin: 24px 0 0; padding-left: 22px; color: var(--muted); line-height: 2; }
.download-options { display: grid; gap: 14px; }
.download-option { min-height: 150px; display: grid; grid-template-columns: 1fr auto; align-items: center; gap: 6px 20px; padding: 26px 28px; border: 1px solid var(--line); border-radius: var(--radius); background: var(--surface); cursor: pointer; text-align: left; transition: transform .2s ease, border-color .2s ease, background .2s ease; }
.download-option:hover { border-color: var(--accent); background: #11243b; transform: translateX(5px); }
.download-option span { color: var(--accent-strong); font-size: 13px; font-weight: 700; }
.download-option strong { grid-row: 2; font-size: 20px; }
.download-option small { grid-column: 2; grid-row: 1 / 3; color: var(--muted); }

footer { width: var(--content); min-height: 130px; display: grid; grid-template-columns: 1fr auto auto; align-items: center; gap: 34px; margin: 0 auto; border-top: 1px solid var(--line); color: var(--muted); font-size: 12px; }
.footer-brand { color: var(--text); }

dialog { width: min(440px, calc(100vw - 30px)); padding: 0; border: 1px solid var(--line); border-radius: var(--radius); background: var(--surface); color: var(--text); box-shadow: 0 28px 90px rgb(2 8 18 / .65); }
dialog::backdrop { background: rgb(2 8 18 / .75); backdrop-filter: blur(6px); }
.download-dialog-card { position: relative; display: flex; flex-direction: column; align-items: center; padding: 34px; text-align: center; }
.download-dialog-card img { width: 80px; height: 80px; border-radius: 18px; }
.download-dialog-card h2 { margin: 22px 0 0; font-size: 28px; }
.download-dialog-card p { margin: 10px 0 22px; color: var(--muted); line-height: 1.6; }
.dialog-close { position: absolute; top: 14px; right: 14px; width: 34px; height: 34px; border: 0; border-radius: 50%; background: transparent; color: var(--muted); cursor: pointer; font-size: 22px; }
.dialog-continue, .dialog-cancel { width: 100%; min-height: 46px; display: grid; place-items: center; border-radius: 999px; font-size: 14px; font-weight: 700; }
.dialog-continue { background: var(--accent); color: #07111f; }
.dialog-cancel { margin-top: 8px; border: 1px solid var(--line); background: transparent; cursor: pointer; }

.reveal { opacity: 0; transform: translateY(24px); transition: opacity .65s cubic-bezier(.16, 1, .3, 1), transform .65s cubic-bezier(.16, 1, .3, 1); }
.reveal.is-visible { opacity: 1; transform: none; }

@media (max-width: 980px) {
  .site-header { grid-template-columns: 1fr auto; }
  .site-header nav { display: none; }
  .hero { grid-template-columns: 1fr; padding-top: 64px; }
  .hero-copy { max-width: 700px; }
  .trust-strip { grid-template-columns: 1fr 1fr; }
  .trust-strip div:nth-child(3) { border-left: 0; border-top: 1px solid var(--line); }
  .trust-strip div:nth-child(4) { border-top: 1px solid var(--line); }
  .capability-story, .security, .download-section { grid-template-columns: 1fr; gap: 48px; }
  .capability-intro, .security-statement { position: static; }
  .capability-nav { grid-template-columns: repeat(4, 1fr); }
}

@media (max-width: 780px) {
  :root { --content: min(100% - 28px, 680px); }
  .site-header { height: 60px; padding: 0 14px; }
  .header-download { padding: 8px 12px; }
  .hero { min-height: auto; padding: 54px 0 40px; gap: 40px; }
  .hero h1 { font-size: clamp(42px, 13vw, 58px); }
  .hero-actions { flex-direction: column; }
  .download-button { width: 100%; }
  .demo-body { grid-template-columns: 1fr; }
  .demo-steps { display: grid; grid-template-columns: repeat(5, minmax(90px, 1fr)); overflow-x: auto; border-right: 0; border-bottom: 1px solid var(--line); }
  .demo-steps button { white-space: nowrap; }
  .demo-stage { min-height: 390px; padding: 22px; }
  .signal-map { gap: 7px; }
  .signal-node { min-width: 60px; min-height: 62px; }
  .trust-strip { grid-template-columns: 1fr; }
  .trust-strip div + div, .trust-strip div:nth-child(3), .trust-strip div:nth-child(4) { border-left: 0; border-top: 1px solid var(--line); }
  .section { padding: 94px 0; }
  .usecase-grid { grid-template-columns: 1fr; grid-template-rows: auto; }
  .usecase-main { grid-row: auto; min-height: 440px; padding: 28px; }
  .case-flow { grid-template-columns: 1fr; justify-items: start; margin-top: 42px; }
  .case-flow i { width: 1px; height: 22px; margin-left: 14px; }
  .capability-nav { grid-template-columns: 1fr 1fr; }
  .capability-panel { min-height: 450px; padding: 24px; }
  .capability-visual, .privacy-visual, .queue-visual, .identity-visual { min-height: 220px; flex-wrap: wrap; padding: 20px; }
  .queue-visual i, .identity-visual i { width: 22px; }
  .security-rules article { grid-template-columns: 1fr; gap: 10px; }
  .download-section { padding-bottom: 96px; }
  footer { grid-template-columns: 1fr; gap: 10px; padding: 32px 0; }
}

@media (prefers-reduced-motion: reduce) {
  html { scroll-behavior: auto; }
  *, *::before, *::after { animation-duration: .01ms !important; animation-iteration-count: 1 !important; transition-duration: .01ms !important; }
  .reveal { opacity: 1; transform: none; }
}